pekko/akka-docs/scala/code/akka/docs/dispatcher/DispatcherDocSpec.scala

package akka.docs.dispatcher

import org.scalatest.{ BeforeAndAfterAll, WordSpec }
import org.scalatest.matchers.MustMatchers
import akka.testkit.AkkaSpec
import akka.dispatch.PriorityGenerator
import akka.actor.Props
import akka.actor.Actor
import akka.dispatch.UnboundedPriorityMailbox
import akka.event.Logging
import akka.event.LoggingAdapter
import akka.util.duration._
import akka.actor.PoisonPill

object DispatcherDocSpec {
  val config = """
    //#my-dispatcher-config
    my-dispatcher {
      type = Dispatcher             # Dispatcher is the name of the event-based dispatcher
      daemonic = off                # Toggles whether the threads created by this dispatcher should be daemons or not
      core-pool-size-min = 2        # minimum number of threads to cap factor-based core number to
      core-pool-size-factor = 2.0   # No of core threads ... ceil(available processors * factor)
      core-pool-size-max = 10       # maximum number of threads to cap factor-based number to
      throughput = 100              # Throughput defines the number of messages that are processed in a batch before the
                                    # thread is returned to the pool. Set to 1 for as fair as possible.
    }
    //#my-dispatcher-config
    
    //#my-bounded-config
    my-dispatcher-bounded-queue {
      type = Dispatcher
      core-pool-size-factor = 8.0
      max-pool-size-factor  = 16.0
      task-queue-size = 100         # Specifies the bounded capacity of the task queue
      task-queue-type = "array"     # Specifies which type of task queue will be used, can be "array" or "linked" (default)
      throughput = 3
    }
    //#my-bounded-config
    
    //#my-balancing-config
    my-balancing-dispatcher {
      type = BalancingDispatcher
    }
    //#my-balancing-config
  """

  class MyActor extends Actor {
    def receive = {
      case x ⇒
    }
  }
}

class DispatcherDocSpec extends AkkaSpec(DispatcherDocSpec.config) {

  import DispatcherDocSpec.MyActor

  "defining dispatcher" in {
    //#defining-dispatcher
    import akka.actor.Props
    val dispatcher = system.dispatcherFactory.lookup("my-dispatcher")
    val myActor1 = system.actorOf(Props[MyActor].withDispatcher(dispatcher), name = "myactor1")
    val myActor2 = system.actorOf(Props[MyActor].withDispatcher(dispatcher), name = "myactor2")
    //#defining-dispatcher
  }

  "defining dispatcher with bounded queue" in {
    val dispatcher = system.dispatcherFactory.lookup("my-dispatcher-bounded-queue")
  }

  "defining pinned dispatcher" in {
    //#defining-pinned-dispatcher
    val name = "myactor"
    val dispatcher = system.dispatcherFactory.newPinnedDispatcher(name)
    val myActor = system.actorOf(Props[MyActor].withDispatcher(dispatcher), name)
    //#defining-pinned-dispatcher
  }

  "defining priority dispatcher" in {
    //#prio-dispatcher
    val gen = PriorityGenerator { // Create a new PriorityGenerator, lower prio means more important
      case 'highpriority ⇒ 0 // 'highpriority messages should be treated first if possible
      case 'lowpriority  ⇒ 100 // 'lowpriority messages should be treated last if possible
      case PoisonPill    ⇒ 1000 // PoisonPill when no other left
      case otherwise     ⇒ 50 // We default to 50
    }

    // We create a new Priority dispatcher and seed it with the priority generator
    val dispatcher = system.dispatcherFactory.newDispatcher("foo", 5, UnboundedPriorityMailbox(gen)).build

    val a = system.actorOf( // We create a new Actor that just prints out what it processes
      Props(new Actor {
        val log: LoggingAdapter = Logging(context.system, this)

        self ! 'lowpriority
        self ! 'lowpriority
        self ! 'highpriority
        self ! 'pigdog
        self ! 'pigdog2
        self ! 'pigdog3
        self ! 'highpriority
        self ! PoisonPill

        def receive = {
          case x ⇒ log.info(x.toString)
        }
      }).withDispatcher(dispatcher))

    /*
    Logs:
      'highpriority
      'highpriority
      'pigdog
      'pigdog2
      'pigdog3
      'lowpriority
      'lowpriority
    */
    //#prio-dispatcher

    awaitCond(a.isTerminated, 5 seconds)
  }

  "defining balancing dispatcher" in {
    val dispatcher = system.dispatcherFactory.lookup("my-balancing-dispatcher")
  }

}